When the Pacific Ocean warms and cools with El Niño and La Niña, we see global temperature rise and fall. This pattern of ocean temperature variability plays into a long-term trend of rising global surface temperatures.

It’s natural to associate drought with heat and with summer, but drought also impacts us during winter months. Winter wheat yields are declining, and the Mississippi River is approaching an all-time low. Understanding drought conditions and how they are affecting us is part of being “climate smart.”

Melt ponds, snow loss, and other warming-induced changes are making the surface of the Greenland Ice Sheet far less reflective in the summer than it was even a decade ago. The darker ice surface absorbs more sunlight than it once did, accelerating warming and melting.

The 2012 Arctic sea ice extent was nearly 50 percent smaller than the long-term (1979-2000) average. For sea ice to have shrunk to half its historic summer extent is as much a transformation of the environment as if half the forests of New England had been replaced by cactus.

On a yearly basis, Arctic temperatures are strongly influenced by natural climate patterns, including the Arctic and North Atlantic Oscillations. Over the span of a decade, though, Arctic amplification of climate change is evident: no part of the Arctic was cooler than the long-term average.

In June 2012, snow cover extent over Eurasia and North America hit a new record low. It is the third time in five years that North America has set a new record low, and the fifth year in a row that Eurasia has. The rate of snow cover loss over Northern Hemisphere land areas in June between 1979 and 2012 is -17.6% per decade—a faster decline than September sea ice loss over the same period.

Few real-world signs of climate change are easier to read than changes in the growing season of familiar vegetation. Most of the high-latitudes of the Northern Hemisphere are experiencing longer growing seasons now than they did more than two and half decades ago.